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std::basic_stringbuf<CharT,Traits,Allocator>::swap

void swap( basic_stringbuf& rhs );
(since C++11)
(until C++20)
void swap( basic_stringbuf& rhs ) noexcept(/* see below */);
(since C++20)

Swaps the state and the contents of *this and rhs.

The behavior is undefined if Allocator does not propagate on swap and the allocators of *this and other are unequal.

(since C++11)

Parameters

rhs - another basic_stringbuf

Return value

(none).

Exceptions

May throw implementation-defined exceptions.

(since C++11)
(until C++20)
noexcept specification:
noexcept(std::allocator_traits<Allocator>::propagate_on_container_swap::value
|| std::allocator_traits<Allocator>::is_always_equal::value)
(since C++20)

Notes

This function is called automatically when swapping std::stringstream objects, it is rarely necessary to call it directly.

Example

#include <sstream>
#include <string>
#include <iostream>
#include <iomanip>
 
int main()
{
    std::istringstream one("one");
    std::ostringstream two("two");
 
    std::cout << "Before swap, one = " << std::quoted( one.str() )
              <<  " two = " << quoted( two.str() ) << '\n';
 
    one.rdbuf()->swap(*two.rdbuf());
 
    std::cout << "After  swap, one = " << quoted( one.str() )
              << " two = " << quoted( two.str() ) << '\n';
}

Output:

Before swap, one = "one" two = "two"
After  swap, one = "two" two = "one"

See also

constructs a basic_stringbuf object
(public member function)
(C++11)
swaps two string streams
(public member function of std::basic_stringstream<CharT,Traits,Allocator>)

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